This invention relates to improvements in imaging a body and, more particularly, to an apparatus and method for obtaining improved body imaging including minimization of exposure of the body to the radiation used in performing the imaging.
In recent years significant advances have been made in techniques for imaging internal portions of a body using radiation such as x-rays. The radiation penetrates into the body and the properties of the internal portions of the body are determined from the radiation that is either transmitted through the body or reflected from the body, depending upon the type of radiation and system employed. Many such equipments involve the use of a means for converting the radiation obtained from the body (either transmitted through or reflected from the body) into an electronic video signal which is, in turn, displayed to obtain a television-type image of the body internal structure. For example, in an x-ray imaging system, the x-rays transmitted through the body may be detected and converted to an electronic video signal using a scintillation detector and a video generator, and the video signal can be displayed to provide a "real time" image of the body internal structure.
An important consideration, when using radiation to image the internal structure of a body, is to minimize the amount of radiation to which the body is exposed, especially when the body is a human patient. The dangers of substantial exposure to certain types of radiation are well known, and it is always desirable to minimize risks (regardless of the type of radiation used) by minimizing exposure of the body being examined. This objective is also compatible with saving energy. A counterveiling consideration, however, is the inadequate detected signal level that may result from using a radiation source of unduly low intensity. A lower signal level results in a lower signal-to-noise ratio, and the consequence can be a poorer quality of the ultimately presented image.
It is among the objects of the present invention to minimize the radiation to which a body must be exposed in order to obtain a resultant displayed image of at least a given effective quality. It is also among the objects of the present invention to improve the video display of images obtained using penetrating radiation.